Friedberg @ 00:24:28Right
health
If residents of major cities largely remain locked down for the next 3–4 weeks from March 14, 2020, local epidemic curves in those cities will follow China’s pattern and begin to flatten within "a couple of weeks." Additionally, within the next few months (by mid‑2020), IgG antibody tests being produced in China and already used in Italy will be shipped to and used in the United States to measure how many people have been infected, after which the epidemiological situation will start to clarify and resolve.
a couple of weeks away, hopefully from, from that happening, if everyone kind of stays locked down...we'll find that out over the next couple of months as these IgG tests get produced in China. They're getting shipped over here right now. They're in Italy right now being used on the front lines. And we'll start to use those to identify how many people actually are infected. And things will start to resolve.
Explanation
Assessment of the “lockdown → China‑style curve flattening” part
- In many major U.S. metros (e.g., New York City, Seattle, Detroit), stay‑at‑home orders and closures were imposed in the third week of March 2020 and widely followed for several weeks. New York’s “PAUSE” order began March 22, and similar statewide or citywide stay‑at‑home orders were issued in Washington and Michigan on March 23–24. (en.wikipedia.org)
- In New York City, reported COVID‑19 cases rose exponentially through mid‑March but began slowing the week of March 22, with case rates for most adult age groups peaking in the week of March 29—roughly two weeks after March 14—and then declining. (cdc.gov)
- That pattern—sharp growth followed by a peak and flattening within a few weeks of aggressive NPIs—matches the qualitative pattern seen earlier in China, though with local differences in timing and severity.
Assessment of the “IgG antibody tests will be shipped here and clarify how many were infected” part
- The FDA authorized the first COVID‑19 IgG/IgM serology test (Cellex qSARS‑CoV‑2 IgG/IgM Rapid Test) on April 1, 2020, and by mid‑April multiple additional serology assays (including some from Chinese manufacturers such as Autobio Diagnostics) had Emergency Use Authorizations. (fda.gov)
- By late March through May 2020, the CDC and others were already running large U.S. seroprevalence studies using IgG tests to estimate how many people had been infected, which showed infections far exceeding reported case counts and materially improved understanding of the epidemic. (jamanetwork.com)
Conclusion
Both key elements of Friedberg’s forecast—the conditional early flattening of city epidemic curves given sustained lockdowns, and the rapid rollout and use of IgG antibody tests in the U.S. within a few months to quantify cumulative infections—occurred broadly as described, albeit with uncertainties and imperfections. Overall this prediction was directionally accurate.